3
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The bonds are: (I have given pictures of what I mean in case there's any ambiguity that I leave open in these questions. Also so that if you want to number the R groups you've got a head-start)

  • Secondary amides, I suspect I might know the answer, extensive. Example is the one in folic acid.

Secondary amides

  • Tertiary amides. This is one that's a complete mystery to me. Example is the one in leucovorin.

Tertiary amides

  • Sulfonamides. Hydrolysis in this case, should lead a primary amine and a sulfonic acid. Or such is the hope.

Sulfonamide

  • Carboxylic esters. To give a primary alcohol and a carboxylic acid. Basically the reverse of the Fisher esterification.

Carboxylic ester

  • Sulfonyl ester.

Sulfonyl ester

  • Secondary/tertiary amines

Secondary/tertiary amines

  • Ether

Ether

  • Sulfyl ether

Sulfyl ether

Now if you're wondering how exactly is this question relevant? As it might sound pretty random for me to just ask this question but it's incredibly relevant to drugs when it comes to their tendency to be hydrolysed in the stomach.

The simple fact is that I'm likely to come up with other questions so if it's possible for you to give me a guide for figuring out this stuff, or estimating it, please do share! If you do this and I can follow it, I will instantly accept your answer as the answer! Providing me with a decent ref will also win you points.

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  • 2
    $\begingroup$ This source contains a decent amount of information on the hydrolysis kinetics of some types of functional groups, though not all those mentioned in your question. $\endgroup$ – Nicolau Saker Neto Apr 19 '14 at 13:32
  • $\begingroup$ It has been shown that the stomach empties between 30 min and 1 hour after a meal (with some latitude). It would be better to restrict your time to 1 hour. Also the pH of the stomach is between 1 and 2 for most people. $\endgroup$ – LDC3 Apr 19 '14 at 13:48
  • $\begingroup$ @LDC3 My lecturers tend to teach me 1-3 hours. Plus I know I personally whenever I take my meds on a incompletely empty stomach I get severe indigestion, 1 hour doesn't do it for me, more like 2 hours at least so that gives me some evidence to the contrary to your theory. Like 1 hour with some latitude to me is +/- 30 mins so yeah I don't know where you're getting your info. Please do show me. $\endgroup$ – BH2017 Apr 19 '14 at 14:19
  • $\begingroup$ @NicolauSakerNeto thanks. It really does help. Still (as I see you're not putting this forward as an answer) I'd like a nice concise (like 3 paragraphs max) method for estimating the percentage of a functional group that gets hydrolysed in a set period of time. $\endgroup$ – BH2017 Apr 19 '14 at 14:22
  • $\begingroup$ @LDC3 read vivo.colostate.edu/hbooks/pathphys/digestion/basics/… it says 4-5 hours for complete stomach emptying so it's saying my estimate is a bit low. Plus the pH depends on whether you just ate or not. $\endgroup$ – BH2017 Apr 19 '14 at 15:27

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